Fertilizer containing lime nitrogen and tankage material.



UNITED STATES PATENT FEIQE.

FRANK S. WASHBURN, OF NASHVILLE, TENNESSEE.

FERTILIZER CONTAINING LIME NITROGEN ANI? TAINKAGE MATERIAL.

1,135,639. No Drawing I To alZ whom it may concern:

Be it known that I, FRANK S. \VAsi-iBUim, a citizen of .the United States, residing at Nashville, in the countyof Davison and treating low grade tankages and similar fertihzing materials with commercial calcium cyanami'd, commonly known as cyanamid, and has for its object the production of an "improved product which shall be drier than v. the ordinarytanloige, richer in nitrogen and shows'a higher nitrogen availability than the original tankage, It will also be free from the 'disiulvantages of mixing the raw 1 material with other fertilizer materials and y at the same time will facilitate the distributionof cyanamid upon the soil.

To these ends the invention consists in 'the' novel steps constituting my process as lon continuedfrcookin ())!'ZItiOIl. i b h well as in an improved resulting product, all of which willbe more fully hereinatter disclosed, anil par ticularly pointed out in the claim I alrnorder that the object of my invention may bemore fully emphasized I might say that l; propose to eliminate the following objections which exist in the manufacture and application of low grade tankagefor fertilize'r. purposes the drying of low grade tankage is costly and tedious, tor -l11 general 1t is produced from animal and vegetable waste organic materials, which are oi a moist and sticky consistency. It is sometimes found necessary to add to certain classes of these materials .in the course of Specification of Letters I'atent.

Patented Apr. 13, 1915.

Application filed November 17, 1914. Serial No. 872.627.

often appear on the market containing as much as 20% moisture, which makes them very ditiicult to handle in the fertilizer industry. It is sometimes found advisable to reduce the moisture content to 15 to 20% in the direct fired drier, and then spread the materials on a large floor where they are subjected to atmospheric drying for a period of from six to eight weeks in order to reduce their moisture content down to such limits that they can be conveniently usedin fertilizer compounding. Such low grade tankages can be divided into the two classes: animal and vegetable. The low grade animal tankage contains in each 100 pounds a nitrogen content equivalent to from 6 to 8 pounds of ammonia, and a phosphorus content equivalent to 10 to 6 pounds of phos phoric acid. The vegetable tankage com monly known as garbage tankage. contains in each hundred parts nitrogen equivalent to 2--2 parts of ammonia. e, therefore, see that the nitrogen content of these materials is very low. Manufacturers and agriculturists prefer materials with a much higher nitrogen content.

The nitrogen content in the tankages does not show a particularly high availability as tlet'lt'ltthbi the ordinary chemical methods, this availability averaging from .20 to 50% for garbage tankage, and 50 to 70% for low grade animal tankage. It is quite desirable that this availability be increased somewhat before the tankages are placed upon; the

.market.

Cyanamid itself contains a considerable quantity of basic lime, which when mixed with acid phosphate in excess of certain predetermined proportions tends to change the soluble forms of phosphoric acid to insoluble ones. Also cyanamid is a rather finely ground. dusty material, and in compounding with other fertilizers it is found desirable to eliminate this dust as much as pos-- mercial cyanamid or lime nitrogen. found that the proportions which yield a very good result are about 100 parts of said damp tankage to about 17 parts of cyanamid or llme nitrogen. The cyanamid or lime nitrogen has the property of fixing the free moisture in the tankage in a stable chemical form and thereby removes the moist and sticky nature of the tankage. I have found that if a mixture, such.as the above, is prepared, the resulting product made of 100 parts of 20% moisture tankage and 20 parts of cyanamid or .lime nitrogen will show 10% of moisture after being stored in for two weeks, and if this bulk storage is permitted to last for four weeks, the "re- Sulting product will contain only 5 to 7% of free moisture. A quantity of moisture as low as this renders tankage free from objeption to moisture content, and it enables it td be mixed without trouble with other fertilizer materials. I find this mixture seems to be chemically fixed and not removed from 'I i the mass, for there seems to be practically no diminution in the total Weight ofthe mixed product. 7

The basic character of the cyanamid neutralizes any free acids which'might exist in the tankage, and thereby loses its alkalinity;

practically all of these tankages contain amnino acids, which also perform neutralizing of the lime and We, therefore, find that when such cyanamid or lime is mixed with the tankage its alkalinity is much reduced and we can, therefore, mix the tankagecyanamidproduct with acid phosphate without any fear of combination of the lime in the cyanamid with the phosphoric acid ip the acid phosphate.

Cyanamid contains about 20% of nitrogen,- so that this mixture of the high nitrogen content cyanamid with the low nitrogen content tankage yields a product containing a higher percenta e of nitrogen than the tankage itself, there y producing'a product ,of considerably more value than the' tankage itself, and at the same time cutting down transportation charges per unit of nitrogen contained.

The nitrogen in cyanamid shows as avail- 11 such a mixture as I have describedwe also find that the particles of cyanamid become attached to the particles of tankage, thereby largely eliminating'the dusting featu'tesof the cyanamid and so facilitating its mixture with other fertilizer materials in the compounding of complete'fertilizer. We thus seethat by the mixing of cyanamidor lime nitrogen with tankage we obtain a prodnot of much lowerfree moisture content, higher nitrogen content and higher availa-- bility than the original tankage, and at the same time we have so altered the cy namid that it no longer shows any cons'derable tendency to change soluble phosphates into insoluble phosphates, and we are eliminat ing the dusting feature entirely from it. The mixture in this way is of more value than either of the two materialsseparately for the compounding of complete fertilizers, and possesses none of the possible disadtaining p os horic materia and fixed moisture, and S11 cient crude cyanamid to have fixed said moisture, substantially as dedescribed.

In testimony whereofI afiix my signature,

in presence of two witnesses,

I FRANK1SLWASHBURN. Witnesses: 4 I

G. U,- Scnmzra1;z, .A: D I EMQ 

